Here in Beantown, one of the subway lines has been closed for a month for renovations, including substantial track replacement.
The line has just re-opened, but is running at about half-speed due to what management says is that the new rails have to be "broken in" before trains can be run at full/normal speed.
Just curious if all new railroad rails require a "breaking in" period ?
Never heard of such crap on the major railroads in the U.S. and Canada! I watched the BNSF install the "sho-fly" for the new, much longer bridge, over the Illinois Tollway, here in Western Springs (about 2 years ago). In talking to the MoW Foreman on a Sunday evening, after they had finished "moving over" main track 3, and connecting each end to the "sho-fly" (they did one track at a time on weekends), he stated that the first train through the "new" main Track 3, would be at 50MPH, then once the rail joints had been thermite welded (after about 2 hours), train speeds would be back to 75/79 MPH. All that had taken place between a Friday night through a Sunday evening.
The same thing happened in reverse, when the complete new bridge was finished, and the "sho-fly" was removed. All new CWR, and once any/all track joints had been thermite welded together, the track speed was back to normal.